(3.07) The summer monsoon brings 80% of India\'s rainfall and is essential for t
ID: 2936776 • Letter: #
Question
(3.07) The summer monsoon brings 80% of India's rainfall and is essential for the country's agriculture.Records going back more than a century show that the amount of monsoon rainfall varies from year to year according to a distribution that is approximately Normal with mean 852 millimeters (mm) and standard deviation 82 mm.
Use the 68-95-99.7 rule to answer the following questions.
Step 1:
Between what values do the monsoon rains fall in 95% of all years? Between 770 and 934 mm. Between 164 and 1540 mm. Between 688 and 1016 mm. Between 606 and 1098 mm.
Step 2:
How small are the monsoon rains in the driest 2.5% of all years? Less than 770 mm. Less than 688 mm. Less than 21.3 mm. Less than 606 mm. (3.07) The summer monsoon brings 80% of India's rainfall and is essential for the country's agriculture.
Records going back more than a century show that the amount of monsoon rainfall varies from year to year according to a distribution that is approximately Normal with mean 852 millimeters (mm) and standard deviation 82 mm.
Use the 68-95-99.7 rule to answer the following questions.
Step 1:
Between what values do the monsoon rains fall in 95% of all years? Between 770 and 934 mm. Between 164 and 1540 mm. Between 688 and 1016 mm. Between 606 and 1098 mm.
Step 2:
How small are the monsoon rains in the driest 2.5% of all years? Less than 770 mm. Less than 688 mm. Less than 21.3 mm. Less than 606 mm.
Explanation / Answer
Step 1: According to the 68-95-99 rule, 95% corresponds to a width of 4 standard deviations.
=> 852 - 2*82 and 852 + 2*82
= 688mm and 1016mm.
Step 2: The driest 2.5% are to be found to the left of the 95% area.
=> Less than 688 mm.
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.